ISO 15686-8:2008

Overview

ISO 15686-8:2008 - "Buildings and constructed assets - Service-life planning - Part 8: Reference service life and service-life estimation" provides guidance for compiling, selecting and formatting reference service‑life (RSL) data and for applying those data to calculate estimated service life (ESL) using the factor method. The standard explains how RSL data should be documented (data records), the importance of stating the reference in‑use conditions, and approaches to modify RSLs to reflect object‑specific in‑use conditions. Note: ISO 15686-8:2008 does not prescribe numerical values for the modifying factors (A–G) nor how to derive the modification number - it focuses on data provision, structure and method application.

Key topics and requirements

• Reference service‑life data (RSL data): RSL values must be accompanied by descriptive data about the component, reference in‑use conditions, critical properties, performance requirements and data quality. RSL data are held in a formatted RSL data record.
• Provision and selection of data: Guidance on sourcing RSL data from manufacturers, test laboratories, national approvals, codes, databases and empirical observations; and on evaluating data quality before use.
• Factor method overview: ESL is obtained by modifying an RSL with a combined modifying number that represents differences between reference and object‑specific in‑use conditions.
• Factor categories: The standard structures in‑use influences into categories (examples: inherent performance, design level, workmanship, indoor/outdoor environment, usage conditions, maintenance level). These categories support estimating factors A–G.
• Formatting and reporting: Guidance on how to format general or scattered service‑life data into standardized RSL data records so data are reusable and auditable.
• Supporting materials: Normative and informative annexes include descriptions of factors and categories, example RSL records, worked examples using the factor method and statistical approaches.

Practical applications and users

Who uses ISO 15686-8:

• Designers and architects estimating component longevity for design decisions.
• Asset and facility managers planning maintenance, refurbishment and replacement cycles.
• Manufacturers and product specifiers documenting service life in product declarations and databases.
• Life‑cycle costing analysts integrating ESLs into whole‑life cost models.
• Testing bodies and national authorities compiling or validating service‑life datasets.

Practical value:

• Improves consistency and transparency of service‑life data.
• Enables more defensible ESL estimates for maintenance planning, budgeting and sustainability assessments.
• Facilitates data exchange between manufacturers, assessors and asset owners.

Related standards

• ISO 15686 series (Parts 1, 2, 3, 5, 6, 7; Parts 9 and 10 in preparation)
• Normative references: ISO 6707‑1, ISO 15686‑1, ISO 15686‑2

Keywords: ISO 15686-8, reference service life, service-life estimation, factor method, RSL, ESL, service-life planning, building durability, life-cycle planning.